1. Field of the Invention
The present invention relates to a remote maintenance system, a mail connect confirmation method, a mail connect confirmation program, and a mail transmission environment diagnosis program, which report fault information to a maintenance center by an electronic mail through an internet when a fault is detected by a surveillance unit mounted in a user device, and in particular, it relates to a remote maintenance system, a mail connect confirmation method, a mail connect confirmation program, and a mail transmission environment diagnosis program, which transmit a connect confirmation mail and automatically diagnose a mail transmission environment.
2. Description of the Related Arts
Heretofore, there has been known a remote maintenance system, which reports fault information to a maintenance center by an electronic mail through an internet when the fault of a user device is detected. In such a conventional remote maintenance system, a surveillance agent which is a software to keep a hardware fault and the like under surveillance is mounted on the user device, and the surveillance agent, when detecting the hardware fault and the like of the device, reports fault occurrence to the maintenance center in a remote place by the electronic mail (e-mail) through the internet. The maintenance center informs support personnel that a fault occurrence notice has been received, and the support personnel, upon receipt of the report, confirms the report content, and by carrying necessary replacement parts, goes out to repair the user device so as to provide prompt and appropriate maintenance services.    [Patent Document 1] Japanese Patent Application No. 2002-055850    [Patent Document 2] Japanese Patent Application No. 2003-296135
However, in such a conventional remote maintenance system, to provide prompt and appropriate maintenance service, it is important that the electronic mail to report fault occurrence is reliably transmitted. Nevertheless, in recent years, there have emerged many users who are limited in mail transmission environment due to reinforcement and the like of security measures, and there is a problem that the mail transmission has been limited by the subsequent change of the mail transmission environment in spite of the fact that the electronic mail has been normally transmitted in the beginning of starting the system operation. As such a change of the mail transmission environment, for example, the following is cited. Limit a transmitter by source mail address Limit transmission by authentication (such as SMTP-AUTH, POP before SMTP, and the like) at the mail transmitting time Limit by a transmission size Limit (prohibition of partitioned mail transmission and limit of extension code) for reason of virus check and the like. The POP before SMPT records an IP address having passed through the authentication in the POP server, and when receiving a request for mail transmission, checks a recording list of IP addresses, and if there is an IP address having passed the authentication in the list, receives the request for transmission, and if not, refuses the request for transmission. The IP addresses are deleted from the recording list when a definite period of time has passed. Further, the SMTP-AUTH, when receiving a mail, performs authentication of a user account and a password between the SMTP server and the user device, and only when authenticated, permits the mail transmission. In general, while these limits on the mail transmission environment are often performed by the manager of the network, on the other hand, the user receiving a service using the remote maintenance system often does not know the limits on the mail transmission environment, and as a result, there is a problem in that a trouble occurs highly likely in many cases where an electronic mail showing fault occurrence cannot be transmitted at the occurrence time of hardware fault and the like of the user device.